Warm Audio WA-412 – 4-Channel Microphone and Instrument Preamplifier
The Warm Audio WA-412 delivers four channels of classic “American console sound” in a sleek 1U rackmount chassis. This microphone and instrument preamp offers deep, expressive lows and open, silky highs. Outfitted with 100% discrete 6-pin operational amplifiers and custom Altran USA input and output transformers, the WA-412 delivers incredible sonic performance and outstanding value for money — giving engineers everything their ears could desire.
More Features
The WA-412 provides all the functions users expect from the classic preamps that inspired it — and more. In addition to traditional features such as 48V phantom power, phase reverse, mic/line switching, and a -20 dB pad, each channel includes a TONE switch, which changes the input impedance from 150 Ohms to 600 Ohms, and an output trim control that enables creative gain-staging and saturation shaping.
Better Components
Each channel is equipped with a 100% discrete 6-pin op-amp, socket-mounted for easy replacement or customization. Discrete op-amp circuits are known for their high headroom and low distortion — qualities that the WA-412 fully embodies. Additionally, custom-wound Altran transformers (Made in USA) are used in both the input and output stages, delivering the clear, open character and punchy tone that define the WA-412’s sound.
The careful selection of premium components makes the WA-412 a true studio workhorse, providing first-class audio quality with a touch of vintage console magic on every signal.
Features & Technical Specifications
4-channel microphone and instrument preamplifier
100% discrete, transformer-balanced circuit design
Custom-wound Altran USA premium input and output transformers
X520 discrete op-amp in each channel (socketed and easily replaceable)
Up to 65 dB of gain
Transformer-balanced XLR and active instrument inputs
Transformer-balanced XLR and TRS outputs
TONE switch changes mic/instrument input impedance from 600 Ohms to 150 Ohms
-20 dB pad (affects both mic and instrument inputs)
+48V phantom power
LED metering per channel
Output trim for precise level control and creative saturation
Internal power supply
19” / 1U rackmount chassis


